1
linux/arch/blackfin/kernel/entry.S
Barry Song d86bfb1600 Blackfin: initial XIP support
Signed-off-by: Barry Song <barry.song@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2010-03-09 00:30:48 -05:00

109 lines
2.0 KiB
ArmAsm

/*
* Copyright 2004-2009 Analog Devices Inc.
*
* Licensed under the GPL-2 or later
*/
#include <linux/linkage.h>
#include <asm/thread_info.h>
#include <asm/errno.h>
#include <asm/blackfin.h>
#include <asm/asm-offsets.h>
#include <asm/context.S>
#ifdef CONFIG_EXCPT_IRQ_SYSC_L1
.section .l1.text
#else
.text
#endif
ENTRY(_ret_from_fork)
#ifdef CONFIG_IPIPE
/*
* Hw IRQs are off on entry, and we don't want the scheduling tail
* code to starve high priority domains from interrupts while it
* runs. Therefore we first stall the root stage to have the
* virtual interrupt state reflect IMASK.
*/
p0.l = ___ipipe_root_status;
p0.h = ___ipipe_root_status;
r4 = [p0];
bitset(r4, 0);
[p0] = r4;
/*
* Then we may enable hw IRQs, allowing preemption from high
* priority domains. schedule_tail() will do local_irq_enable()
* since Blackfin does not define __ARCH_WANT_UNLOCKED_CTXSW, so
* there is no need to unstall the root domain by ourselves
* afterwards.
*/
p0.l = _bfin_irq_flags;
p0.h = _bfin_irq_flags;
r4 = [p0];
sti r4;
#endif /* CONFIG_IPIPE */
SP += -12;
pseudo_long_call _schedule_tail, p5;
SP += 12;
r0 = [sp + PT_IPEND];
cc = bittst(r0,1);
if cc jump .Lin_kernel;
RESTORE_CONTEXT
rti;
.Lin_kernel:
bitclr(r0,1);
[sp + PT_IPEND] = r0;
/* do a 'fake' RTI by jumping to [RETI]
* to avoid clearing supervisor mode in child
*/
r0 = [sp + PT_PC];
[sp + PT_P0] = r0;
RESTORE_ALL_SYS
jump (p0);
ENDPROC(_ret_from_fork)
ENTRY(_sys_fork)
r0 = -EINVAL;
#if (ANOMALY_05000371)
nop;
nop;
nop;
#endif
rts;
ENDPROC(_sys_fork)
ENTRY(_sys_vfork)
r0 = sp;
r0 += 24;
[--sp] = rets;
SP += -12;
pseudo_long_call _bfin_vfork, p2;
SP += 12;
rets = [sp++];
rts;
ENDPROC(_sys_vfork)
ENTRY(_sys_clone)
r0 = sp;
r0 += 24;
[--sp] = rets;
SP += -12;
pseudo_long_call _bfin_clone, p2;
SP += 12;
rets = [sp++];
rts;
ENDPROC(_sys_clone)
ENTRY(_sys_rt_sigreturn)
r0 = sp;
r0 += 24;
[--sp] = rets;
SP += -12;
pseudo_long_call _do_rt_sigreturn, p2;
SP += 12;
rets = [sp++];
rts;
ENDPROC(_sys_rt_sigreturn)